As of this writing, Abbas says he's going to submit an application for full U.N. membership to Secretary-General Ban Ki-Moon after his speech on Friday. But Abbas knows that the required nine-vote Security Council majority is significantly in doubt, and that even if it can be secured the United States is publicly committed to vetoing any such resolution. Therefore, the most Palestinians can accomplish is for the U.N. General Assembly to vote to upgrade Palestine to a nonmember observer state. No plans for a General Assembly resolution have been announced—presumably because the Palestinians are still pushing hard for the more ambitious Security Council victory—but there is little doubt the Palestinians could win a majority for one.

It is this nonmember observer status that could cause a showdown over the Palestinians' right to petition international legal bodies. At the U.N. itself, nonmember status would not do much to change the Palestinians' rights and prerogatives, but it could theoretically provide them access to a number of international law enforcement agencies and mechanisms, most notably the International Criminal Court, which was created by a treaty among many nations.

Ambassador Christian Wenaweser, president of the ICC Assembly of State Parties, told the Wall Street Journal that a Palestinian observer state could join the ICC and try to initiate proceedings against Israel under the Statute of Rome. Because Israel is itself not a party to the ICC, Israeli officials cannot be prosecuted on the basis of their Israeli nationality. And so far the Palestinians have not had success bringing criminal action against Israelis for their acts in the Palestinian territories, because the legal status of East Jerusalem, the West Bank, and the Gaza Strip—is internationally undetermined. The ICC essentially ignored a 2009 effort by the Palestinian Authority to get the ICC to take action against Israel regarding the war in Gaza.

However, if the General Assembly were to recognize an observer Palestinian state in its 1967 borders, not only could Palestine become a party to the ICC, it could claim to be the legal sovereign in the occupied territories and seek charges for Israeli actions in those territories on that basis.

At the ICC, Israel would not only be vulnerable to charges regarding unlawful military actions against persons and property, but also for settlement activity, which the Statute of Rome defines as a war crime. It is also potentially vulnerable to charges under the "crime of apartheid," which is defined as "inhumane acts ... committed in the context of an institutionalized regime of systematic oppression and domination by one racial group over any other racial group or groups and committed with the intention of maintaining that regime." That would certainly seem to apply to the social, legal, and political system enforced by Israel in the occupied territories, although the question of intending maintenance of it might be an out for the Israelis on this issue.

The European Union finds itself badly and uncomfortably divided into three camps on the question of nonmember U.N. observer status for Palestine: those opposed, those supporting, and those ambivalent about such an upgrade. The Europeans have been negotiating among themselves to try to find a formula they could unite behind and also provide some diplomatic benefits acceptable to the Palestinians.

European countries worried about Palestinian access to the ICC blocked a Spanish-French proposal for nonmember observer status for Palestine, and there has even been discussion among Europeans about creating a new legal status for the Palestinians that would provide an upgrade in status but block potential access to the ICC and other international legal enforcement agencies.

Even if the Palestinians got nonmember state status at the U.N., which is the maximum they could achieve under the present circumstances, and were able to become party to the ICC, there are serious doubts about their practical ability to bring charges against Israel or Israeli officials. Any request for such charges would be more a diplomatic and political question than a legal one, and both the ICC and prosecutors would be subject to significant domestic and international political pressures that make it hard to imagine such a scenario actually unfolding.

The recent history of the ICC suggests that diplomatic and political realities are more important than ICC membership in prompting such indictments. The Goldstone Report on the Gaza War, for example, accused both Israel and Hamas of serious war crimes, but this was not acted on by the ICC. Opposition came not only from traditional defenders of Israel like the United States and France, but also from Russia and China, who were worried about the potential precedent regarding the behavior of military forces acting against guerrillas or insurgents in heavily populated areas.

By contrast, neither Sudan nor Libya were parties to the ICC, and the areas in which their militaries were operating were, at the time, within the sovereign territory of their governments. This did not prevent the U.N. Security Council from authorizing investigations that led to the indictments of Sudanese President Omar Bashir and Libyan leader Moammar Qaddafi and some of his sons.

Both of these examples strongly suggest that the international diplomatic and political climate is much more important to securing ICC indictments than membership in that organization. And the indictment of Bashir has not been acted on. He even attended the independence ceremony of the new Republic of South Sudan, standing in the presence of U.N. Secretary General Ban and many other world leaders. These precedents suggest that whatever technical advantages the Palestinians might gain from a U.N. upgrade, they will still face significant hurdles to legal action. Under the present international political and diplomatic climate, it's quite difficult to imagine any international law enforcement agency such as the ICC actually bringing charges against Israel.